pressure ridges pushed up by ice move
ments hundreds of miles away. Only skis
can ride the bumps; it is too rough to land
with wheels. The ski-Hercules of VXE6
use a permanent 10,000ft by 280ft skiway
on this ice sheet as their home airfield
throughout the Antarctic summer, flying
a shuttle service all over the continent to
wherever the scientists need a seis
mograph or a sandwich.
A new skiway is being scraped out of the
ice because the present one is being
pushed rapidly towards the sea as the
entire continental ice sheet migrates radi
ally outwards from the Pole. It will be the
second ice airfield to disappear into the
sea since VXE6 made its first landing at
McMurdo in 1955. The strip is known as
Williams Field, in memory of a bulldozer
driver who came upon a patch of thin ice
and went through it.
If VXE6's Hercules do not get airborne
after the 10,000ft skiway runs out, they
can just keep going for another 20 or 30
miles, but it can be a tiresome business
taxiing back to base if the Hercules still
fails to leave the ice.
For about six weeks each year—starting
in October, when the winter night recedes
and the weather improves with spring—
the non-permanent section of the Ross Ice
Shelf is strong enough to support US Air
Force C-141s carrying 50,0001b loads.
After that, only Royal New Zealand Air
Force Hercules, carrying 28,0001b cargoes,
can land during a critical few weeks while
the onset of summer is steadily under
mining the 7ft thick crust of ice, which
finally breaks up.
In one season this temporary ice surface
does not get a chance to become wrinkled
and ridged, so the standard wheeled
C-141s and RNZAF Hercules can touch
down. This is fortuitous because strategic
resupply from Christchurch—some 2,000
miles away—is a painfully slow process
with the high-drag ski-Hercules. They can
carry 16,0001b payloads southbound off
Christchurch's concrete runway, but are
limited to only 6,0001b when flying north
bound off the ice with full fuel because ski
drag prevents them from reaching take
off speed at higher weights.
Where the ski-Hercules really come
into their own is in another form of
"drag". Pilots of VXE6 regularly land
their aircraft out in the middle of the
crevasse-ridden continent. It behoves
them to avoid falling down a hole, so they
"drag" the virgin territory—nose high,
90kt, main skis in the snow.
It is a matter of professional pride
among crews that the drag shall be
straight as a die. If it isn't they might
within a few minutes. The drag goes on for
miles. Then they pull up, fly a circuit and
A ski-Hercules of Antarctic Development Squad
ron Six comes in to land, left. Getting off again,
below, can require rocket boost
peer over the side, looking for crevasse
holes in the drag. Then they attempt to
land in their own tracks. Jokes about
"banana skiways" are not appreciated in
the crew room.
Operations Officer, Commander Joe
Mazza, sums up the problems faced by
VXE6 as high winds (100kt is nothing),
low ceilings, and "whiteouts"—when even
the sky turns white as sunlight is dif
fracted through ice crystal clouds.
"Surface definition can be so bad that
people fall over when walking", says
Mazza. "They literally do not know which
way is up".
Astride the McMurdo skiway there are
black panels set in the ice every 1,000ft.
Mazza explains that in a whiteout all you
can see from the cockpit on the approach
is black panels floating as if in space or on
a video game. Sky, cloud, skiway and
surrounding ice do not exist.
The handling pilot stays on instru
ments. The copilot helps to guide him or
her to touch down. (Yes, "her"—there are
women ski-Hercules pilots, including Lt
Paula Bond, a fully fledged polar tactical
aircraft commander). In a whiteout the
copilot monitors the airspeed and descent
rate and the flight engineer calls the radar
altitude, while the navigator shouts
distance and drift angle. They use the
same trick as the New Zealanders—
aiming for 1,000ft altitude ten miles out,
then establishing a 200ft/min descent rate
down to a "manual autoland".
The US Navy does not have many
Hercules on strength, so the crews tend to
come from anti-submarine backgrounds
on P-3s. "We grow polar commanders
here", says Joe Mazza. The "old man" of
the squadron has only three years' experi
ence on Hercules. It causes some prob
lems, but they learn to do things for which
the Hercules was never designed; and they
learn quickly.
Hercules navigation in Antarctica is by
single Litton inertial reference unit, gyro
compasses, and "grid" maps, plus star
shots to keep gyro precession under super
vision. On-board radar is used a lot. They
FLIGHT International, 12 January 1985 27